Railway signaling.



J, P. BUCHANAN.

gmwnv SIGNALING. APPLICATION FILED JAN. 22' -19l5.

1,140,495. Patented May 25,1915.

2 SHEETSSHEET 1.

IWI'ILNIESSES Q46 fwm .l. P. BUCHANAN.

RAILWAY SIGNAUNG.

-APPL lCATl0N FILED JAN. 22, 19-15.

Patented May 25 1.915.

INVENTOR WITN 1 and 2. Block signals- "UTED STATES PATEN "Q JOHN P. BUCHANAN, or cLEyELimn, 01110, ssxeuoit TO THE UNION swrrcn &

SIGNAL COMPANY, or swIssvaLE, PENNSYLVANIAfA CORPORATION or PENN- sYLvANIA.

RAILWAY sieimmne.

Application filed January 22, 1915'. Serial No.- 3,739.

To all whom it may concern Be it known that 1, JOHN P; BUCHANAN? naling, of which the following is a speci cation.

My invention relates to railway signaling, and particularly to automatic signaling of the type in which the signal for each blockthree indications, viz.,

is adapted to'give proceed, caution, and stop;

More particularly it relates to signaling of this type in which each signal is conof current, the reversals being accomplished by the signal for the block next in advance. It is well understood by those skilled in the art that the circuit for rent for the signal controlling apparatus may include the track rails or may include Y line conductors distinct from the track rails,

the former being polarized track circuit, and the latter as a polarized line circuit.

the polarthe polarif the line which may be operated either on ized track circuit princlple or on ized line circuit principle. Then,

circuit is deranged, as for example due to,

Similar reference characters refer to simi- 15.1 parts in each of theyiews.

Referring first to Fig l,

, ioves inthe direction ofj-"thear j'row, which track is divided into block sectlons A, B,

' to. by any one of the .Wgllkhoirnmeans,

uch as insulated joints "the/track rails in S etc of any 'electromotiveforce l haveshown to batteries E E etc. located at one end ofea-ch. 7 0- trolled by apparatus responsive to reversals .block I also provide a the reversible curknown in the art as a One feature of my inventlon is the provision of apparatus the same battery. Furthermore,

'etc., and N N drawings, Figure 1 g operation'by hand.

block comprising only one track vnected to rail "switch H and wire nal of'which battery is connected torai12. by means of'wire 73, blade 11 have 'h'ere'=; shown a railway track over which traflig' Specification of Letters Patent, I Patented May 25, i915.

of the Well known types are located at 'the' As here shown, each signal is of the one-arm three-position type, although it is understood that two-arm, two-position signals may-equally. well be used. Each block sec tion is equipped with the usual trackcircuit, I

consisting of a source of the track rails and a relay. The sourcesof block section. The track relays located at the other ends of the sections are of-the polarized type, and are designated by the reference characters R HQ, etc. For eachline relay of the polarized type located adjacent thesignal at the entrance to the blockand'des'ignated by the reference characters it M etc. Pole electromotivef r'c changers G G etc., are operatively connected with the'block signals and serve to'u control the polarity of the track-circuit or the line circuit as hereinafter explained. Batteries V V etc., are provided for supplying the operating mechanisms of signals S S etc, with the necessary electrical en'- elrgy, whereas batteries B B etc., are for the purpose of 'supplyi-ng electrical energy to the line circuits. In practice, the two batteries B and V could equally'well be one and for each block section l provide' three double-pole, double-throw switches K etc., anda double polesingle throw switch H H etc; all of these switches are as hereshown arrangedfor Assuming first that able switches are in the positions shown, then K etc., L L

the signaling system is a polarized line sys tem, as the following description wilif sl ow.

'Consi'dering'block B, for example, thetrack circuit is supplied with'signaling current by battery E one terminal of which is con- 65, and the other termiof switch H and wire 66. If the track rails of section B are unoccupied by a train or car, the signaling current will energize the track relay R by flowing from rail 1 through wire 23,911-

1 throughwire-71, blade 10 of 95 the manually operergizing winding of relay 1%, wire 22 to rail 2., Relay R attracts its armature, whereby neutral contacts 44-47, 45-48, and iii-i9 are closed. Contacts 45-i8 and 46-49 of relay R close the following circuit: from battery B through wire 19, blade 21 of knife switch K wire 70, blade'6 of'polechanger G, wire 78, blade 30 of switch L M wire 88, blade127f'of switch N wire wire 79, contact -48 of relayR wire 85,

energizing winding of relay M wire 86, contact iii-.49 of-relay R wire 80, blade 31 of switch L wires 77. and-75, blade 5 of pole-changer G wire 69, blade 20 of switch K wire 18 tovbattery B Thus line relay M is energized, so that contact-51 closes the following circuit: from battery V through wire 89, operating mechanism of.

signal S, wire 82, contact 50-51 of relay 125 to battery V Assume that contact [53-52 of relay 1W is closed when the direction of current through the energizing wind-' of this relay is such as is indicated on the drawing by the polarity ofbattery B3 and the position of pole-changer G which I shall call the normal position of the I have not shown the operating mechanisms of the signals, for I assume these :mechanisms any of the well known types. S n' fiice it to say that the circuit closed by .Ic'o'ntact 50-51 of each relay M is called the" I45 degreecontrol circuit, which means that ";.when this circuit .is closed thegoperating mechanism of, signal- S? drives "the semaphore arm 4, normally biased to a hOIlZOIl- ,tal position indicating stop, to a position at an angle of about 459 from the horizontal, which aspect of the signal 1 called caution.

cuit of the signal is closed, which means that the signal mechanism drives the semaphore arm-4 so as to be at about 90 from the horizontal, givingthe so-called proceed aspect of the signal. When a train enters block B, it short circuits relay R by form ing a low resistance path for the signaling current from rail to rail through the car wheels. Thus relay R is-deenergized, its armature drops and opens its contact 44-47, 45-48, 46-49. The energizingfcircuit 10f relay M is thereby broken and contact 50-51 of relay M opens both, the-90? &5 control circuits of signal-*1 phorearm 4 of signal S thus drops to the horizontal position, indicatin stop to...

the engineer of a; followingtraiu-q vAs the ceed aspect.

The above description shows that my systern-operates as a polarized line system when the switches H, K, L 'and'N arein the posi- When contact 52-53 of relay M is also'closed, then the 90 control cir-v train passes into block as puts signal s to the stop indication by the same sequence of operation, of the relays for block 0.

When the last pair of car Wheels of the train leave'block 'B the short circuit across the track rails of block B is removed and relay B is again energized,--sothat the neutral contacts of this relayagain close. Thus current is again furnished to' relay M but the polarity of this current is opposite in ,direcr tion to the direction assumed above, for pole changer Gr operated by semaphore blade 4 of signal S was reversed as the arm passed through the 45- 0 part of its str0ke. Hence relay M closes only contact 50-51,

or the-45 control circuit. of signal S, Which is thus moved to the caution aspect, where it stays as long as the train is in block C.

When the train enters block D itputssignal S to the stop position, and when it has left block entirely, signal-S is moved to the caution indication by an operation of the apparatus similar to that described hereinbefore. ,As the semaphore arm 4 of signal I S goes-to theicaution or 45 position it again operates the pole-changer G return ing it to the normal position. Thus the current through relay M 'is again normal in directionsothat contact' 52-53 closes, thus 7 closing the 90 contro1 circuit offsignal S3, which causes this Signal to assume the protions' indicated on the drawing. When switches K, L and N are reversed and switches H are'opened-my system will operate as follows: Consider againblock; section B. By opening switch H? and reversing A switches L and K batteryE is connected across the rails "1, 2 through. pole-changer G the connections being: from one ter minal f battery EB through wire 74;,blade 21 of switch K wire 70, blade 6" of polechanger G9, wire 78, blade 30 of switchL wires 67 and 66 to rail 2, and from the other terminal of battery E through wire-72,

blade 20 of switch K wire 69, blade 5 of.

pole-changer. G", wires and. :77, bl'ade 31 'of switch L9,. wires 68 and 65 "to rail 1. Thus signaling current flows through the track rails 1, 2 and, aslong as the track is unoccupied, through relay R, which at tracts its neutral armature and closes therefore its contacts 44-47, 45-48 and 46-49.

cuits for signal S has been transferred from relay Mi -to relay R by switch N Contact The closure of contacts 45-48 and .4c6-i9is immaterial, becausethe control of the cir- Of relay R closes the45 control cir- Gifiltgbf the signal S which circuit is: from firywthroughiwire 89, operating mech-v wires 82and 83, contact was :92; hat 1127 of relay kdi switch N wire 125 to battery V Assuming that the direction ot the current in relay R is such that polarized contact 54T55 closes, this contact closes the 90F"control circuit of signal S causing current to flow from battery V through wire 89, operating mechanism of signal S wire 81, blade 128 of switch N wire 84, contact of l't ,'wire 33, contact l4l7 of relay R wire 97, blade 12''? of switch N wire to battery V Thus, under conditions as assumed above the signal 3- at the entrance to block B gives aproceed indication. l hen a train enters block B, it short circuits relay R the neutral contacts of: which drop, thereby opening both the 45 and the 90 control circuits of signal S so that this signal changes to the stop indication. l i hen the train enters block G, the aspect of signal S is changed from pi'occecl.to stop. Then, as semaphore arm at of signal 5 goes through the 45 to 0 portion of its stroke, it reverses pole-changer G which as pointed out above is operatively conncctwith arm 4 of signal S Thereby the direction of the flow of thesignaling current in the track rails of block 33 is changed, so that when the rear end of the train leaves block B, removing the short circuit from relay R this relay closes its neutral contacts, but the polarized contact 54-5-3 remains open. Thus current is furnished only to the -l5 control circuit and the signal S is caused to give t e caution indication. Similarly when the train enters block D, signal S assumes the stop aspect; and as the train leaves; block C completely signal S assumes the caution aspect. But, as the semaphore time t of signal s moved; from 0 to 45 it again. reverses pole-changer G whereby the direction of the flow of signaling current through block B isagain made normal. This causes contact 54:55 of relay R to close the 90 control circuit 01? signal 53. Thus si nal S is caused to give the clear indication.

K The above description shows that with the switches in the positions assumed my system operates on the polarized track 01rcuit principle.

Referring now to Fig. 2, I have here wn a modified form of signaling system I wherein.. tlie block sections A, B, etc. are

diridedinto sub-sections A and A B and B etc, by means of additional insulated rail joints 3. In addition to the apparatus used in Fig. 1 each block is provided with another track relay P P etc, which has a polarized and a neutral armature, the former actuating contact fingers and 63, the latter controlling contact fingers 56 and 57, another track battery E ',E,etc., and

another double pole, double throw switch W W etc. 'To describe the operation of this system, assume the switches H, K, L, N and pole-changer G long as there is no train in sub-section B,

relay R is energized by the signaling current furnished by battery E the connections between the relay and the rails being the same as shown in Fig. 1. In sub-section B the track circuit is supplied with signaling current by battery E connected to the rails at one end of thesub-section in the same manner as in Fig. 1'. Relay P connected to the traclrrails at the other end of sub-section B by wires 102 and 103,'is energized by this current when there is no train in sub-section B Thus relay P closes its contacts 56-58 and 57- 59, thereby closing the circuit: from battery B wire 18, switch blade 20 of switch K wire 69, blade 5 of wires and 7?, blade 31 of switch L wire 80, contact l6-l9 of relay R wire 86, energizing winding of relay M wire 85, contact ii-48 of relay R wire 96. contact 56-5S of relay P wire 92,

'wire 79, blade of switch L wire 78, blade 6 of pole-changer G wire 70, blade 2-1 of switch K wire 19 to battery B Thereby line 'relayhl of block B is energized and closes contact 50 51. Assume also that the direction of the current through relay M is normal, so that its polarized armature closes the contact 53.-52. Then both the 45 and the control circuits of signal S are closed as described in liig. 1. so that signal S is caused to give the proceed indication. Now, when a train moving in the direction of the arrow enters block B, it short circuits relay R which releases its neutral armature and opens the energizing circuit ciple, and are not mentioned here for that reasonl. Thus, even though relay R is reenergized as the rear of the train leaves sub section B, and closes contacts 45-48 and 46-49, relay M is not energized because its circuit is broken at contact 56' relay tion of flow of the line current, so that when, the train leaves sub sect'ion B anclrelay P closes the line circuit at contact 56 58, r'elay M is suppliedwith current flowing in reverse direction, which causes it to close contact'50-.51 and to open contact 53-62. Thusfonly the 45 Control circuit of signal S? .isclosed and this signal assumes the caution'aspect. Similarly, when the train.

' enters block D it causes block signal S to proceed indication. Thus, with the man And as it.leaves block C f indicate-;-stop.?

completely 1t 'cause'sgsignal S .to assume thecaution/ aspect.- In doing. so, the semaphore of si al S operates tlie"pole changer G whicE- makesithe direction of the current flowing in the line'circ'uit of block B nor- -mal." Relay M closes contact 53 52 and completes thereby the 90 control circuit of signal- S 1. Hence signal S assumes the u'ally operable switches in the position shown in Fig. 2, the signaling system operatesas a polarized line system.

When theswitches K, L, N and W are reversed and the switches H are opened, then the signaling system operatesas follows In.

block B, the track circuit of sub-section B [is supplied with signali'ng'current by battery'EB, one termlnal of which is-connected .to rail 1 by wire 72, blade 20 of switch K wire fit), blade 5 'of poleucha'nge'r G9, wires 7 5 and 7 'L-blade 31 of switch L and wires (i8 and-'65, and the other teIIIl1I1&l0f Wl1lGh 1s connected to rail 2 by wire 74, blade 21.0f', --'switch K wire 70, blade 6 of pole-changer GL'wire 7-8, blade. 30 of switch L and wires '67 and '66.: Assume the direction of flow of this current to be such that the polarized armature of relay P3 will swing contact contacts then furnlshes signahngcurrent to the track circuit. ofsub-section B, one-terminal belng connected to-raillby wire 38, blade 42 of. "switch VV wire 93, contact 57-59 of relay -P ',;wire. 94, contact 62-+63 of relay'PB, wires '98 and .90, and theother terminal being con- .nected to'ra'il 2 by wire 39, blade 436i? switch .W wire 92, contact 56 58 of relay P3, wire 95, contact 61-6 0 of relay P wires 100,. 99, and 91. Assume-the polarity of this 'Iclaim'is: p, p I

" 1. In combination, a section of railway track, a track circuit and a line circuit for current-to be such that, when there is no train i'n-sub-section B, relay B is energized normally, ile. both the neutral and the olarizedcont'acts are-closed. Then the 45 and the-90" control circuits of signal S? are closed a s-described in Fig. 1, whereby signal S is caused to give the 1.- proceed indica-' tion, When atram moving in the dlrectioni fingers 6O and 63 to this left, so as to close 61'-60'an'd 62 -63. Battery E of the arrow enters block .13, relayR -is'shost circuited and opens both the '90? and 45 control" circuits of signal S atcontact-44 s 47 .Th'us semaphore arm 4 OjsignalTSfli'Q released'and drops tothe horizontalposi tion. As the trainentersjsub-section B of block B, it short circuits" relayP ,gwhich' opens contacts -5658' and 57-59 breaking thereby the connection ofba'ttery i tothe I track rails; Relay R thus remains open" so .76 that signal S continues to indicate St/OPP ,As the train enters block C it causes signal S to assume the stop indication At'the same time pole-changer G is" reversed, .-so

that the signaling current, which ag'ainfiows in relay P? asthetrain leaves subfsec t onB entirely, is reversed in direction. I Hencethe polarized armature of relay P causes c'o'ntact fingers 60 and 63 to swing to the right,

whereby the connections of battery E to the track 'rails'are reversed. Consequently signaling current flows in the track circuit of subsection-B in the opposite direction,

and relay R closes contact 44-47, but opens -contact';54.55. Thus only thel45. control;. circuit of. signal Siis closed, which causes l the signal to assume the caution aspl ct.

' Similarly, as the train enters block D, it puts- -the signal S for that block to the stop indi cation, .thusreversing pole ch'anger G, which controls the direction of flow of. signaling current in section Rel'ayfP then closes, hence s1gnal S 18 caused to assume the caution aspect..- "l hereby 'the ,p'o'le chan'genGr is thrown intoits normal posl;

tion and the .direction'of flow'lof signaling current in sub-section B -is again reversed so that contact fingers 60 and 63. of relay P are shifted. to 'make contact to the left.- Thus. current through sub-sectionB is re versed, causing relay-"R to close the control circuit of signal S at contact 54-55, whereby signal S is-returned to theproceed indication:

The above description shows that the signalin system with the various manually opera le switches in the positions specified operates on ciple. 1 r

Although I have herein shown and de-*' spirit'and scope'of my invention; Having. thus described my inve the polarized track circuit prinscribed only two ,forms of signaling system embodying my invention, it is understood. that various changes'and modifications-may be made therein within the scope of thappended claims without departing from the tion the section, a signal for the section, and

' a linecircuit for the section,

track, means for dividing't' time into subsections, a track circuit for 'ea sub-section,

asignal tor the section, and means for control-ling said signal by the track circuits alone or by the track circuits and the line circuit.

3. In combination, a section of railway. track, a track circuit for the'section including a track relay responsive to reversals of current, a line circuit extending through the section and controlled by said track relay and including a line relay responsive to reversals of current, means for supplying current to either the track circuit alone or to a both the track circuit and the line circuit, means for reversing the current in the track circuit when current is supplied to the track circuit only and for reversing the current in the line circuit when current is supplied to both circuits, a signal for the section, and means for controlling said signal by the track relay or by the line relay according as the track circuit alone is energized or both circuits are energized.

4.111 combination, a section of railway track divided into sub-sections, a track circuit for each sub-section including a track relay responsive to reversals'of current, a line circuit extending through the section and controlled by the track relays of the the last-mentioned track circuit when current is supplied to the traclrcircuit only and for reversing the current in the line circuit when current is supplied to the track'circuits and the line circuit, a signal for the section, and means forcontrolling, said signal by the track relay of the first sub-section or by the line relay according as v the track circuits alone are energized or both the line circuit and the track circuitsare energized.

' .5. Incombination, a section of a railway track, a track circuit for the section including a track relay responsive to reversals of.

current, atrack battery, a line circuit for the section controlled by said track relayand including a line relay responsive to reversals of current, a line battery for the line circuit,

a pole-changer, switches and conductors for connecting the track battery directly with the track rails and the line battery with the line circuit through the pole-changer, or for disconnecting the line battery from the line circuit and connecting the track battery with the track rails through the pole changer, a-

signal, and means for controlling Saidg'sig nal by the track relay or by the line-relay;

6. In combination, a section of aj-raihvay track which section is .divided into 'sub sec-' tions, a track circuit for each sub-section including a track relay responsive to reversals of current, a track battery for each sub-section, a line circuit extending througlr the section and controlled by a neutral contact of each track relay, said line circuit includ- 'ing a line relay responsive to reversals of current, a line battery for the line circuit, a

pole-changer, switches and conductors for connecting the track battery for the subsection farthest in advance directly with the track rails and the line battery with the line circuit through the pole-changer, or for disconnecting the line battery from the line circuit and connecting the last-mentioned track batterywith the track'rails through the pole-changer, means for connecting each' I remaining track battery' directly with the track rails of the corresponding sub-section or for connecting each of said remaining track batteries with the track rails through contaots of the track relay for the sub-section in advance said contacts constituting a pole-changer, a signal for the section, and

means for controlling said signal by. the track relay for the rear sub-section or by the line relay.

7.111 combination, a railway track di vided into sections, a signal for each section,

a trackicircuit for each section, including a source of electromotive force and a track relay responsive to reversals of current, a line circuit for each section comprising two line wires extending through'the track section, a source of electrouiotive force for the line circuit and a line relay responsive to reversals of current connected to the line wires, a reversing switch for each section' operated by the signal for the following track section for reversing the flow of currentin the circuit in which it is connected, means for connecting said reversing switch eitherinto the traclncircuit or into the line circuit, a signal controlling circuit adapted to be controlled by either the track relay or the line relay, and means for switching the controlling circuit of the signal from one relay to the other.

8. In=combination, a railway track divided into sections, each section being divided into sub-sections, a signal" for each section, a'

track circuit for each sub-section including i'is a source of electromotive' force and a traclci allel to the track sections, a source of electro f motive rorce for the line circuit and='=c'a line relay responsive to reversals of current connected to the line wires, said line cir ouit being controlled by the track relay for each sub-section, means controlled by relay responsive to eversals of current, a

line circuit comprising two linewires par- 20 electromotive force and a track relay responsive to reversals of current, a l1ne=c1rthe first sub-section for reversing the how i the track relay of eachsub-section except of current through the track'circuit of the i T preceding sub-section, a reversing switch for each section operated by. the'signal for the track section in advance for reversing the flow -of current in the circuit in which it is lccninect-ed, means for connecting sald revers ing switch elther into the track c1rcu1t of the last sub section or'into the line circuit,

a-signal controlling circuit adapted to be controlled by contacts of either the track relay of the first sub-section or the line relay, and means for switching the controlling "I other;

circuit of the signal-from one relay to the "9. In combination, 'a'sectionflof railway track, a signal for the section stationed adjacent the entrance to the section, a track circuit for thesection including. a source of cuitfextending through the section, asource of 'el'ectroniotive' force for the line c1rcu1t anda line relay responsive to reversals of '1 current connected to the line c1rcu1t, -a cur-.,

rent reversing device, means, for connecting said. reversing device either into the track.

circuit or into the line 'cir'cuit, a caution circuit and a proceed circuit for said signal, both of s'aid. .circuits being arranged so as toinclude either the contacts ofthe line relay or the contacts of thetrack relay, and.-

means for switching the controlling circuits of the signalfrom' one relay to the other;

10. In combination, a railway track divided' into. sections .byjmeans of insulated joints, and divided into-sub-sections bymeans of additional insulated joints, asign'al for r each section stationed adjacent, the entrance to each section, a "track circuit for each subsection, including a source of electromotive force and a track relay responsive to reversals ofcurrent, a line circuit for eachsection comprising two line. wires parallel to thesection, a source of 'electromotive force. for-each linefcircuit and a line relay for each section responsive to reversals of current and-connected to the line Wires, said line circuit being controlled by, the trackthe track section in advance for reversing the flow of current in the circuit in which -it is connected', means for connecting said reversing switch either into the track circuit of the last sub-section of the track section or into the line circuit, circuitsfor conso' I trolling each signal actuating mechanism one to operate the signal to give the-caution indication and another to operate the signal to give the clear] indication, both of saidcircuits being arranged vso as to include 1 either thecontacts of the line relay orthe 1 contacts of: the-first track relay of the section, and-means for each section for switching the controlling circuits of thesignal fromon'e relay to the other.

In testimony whereof I aifix mysignature in presence of two witnesses.

, JOHN P. BUCHANAN.

Witnesses: j" I, i

CHARLES W. Rom,

F.- B..W'1NGAND. 

